Neuroleptic Malignant Syndrome

EMCrit Wee – Neuroleptic Malignant Syndrome (NMS) Explosion

  • Rare condition compared to serotonin syndrome
  • Idiosyncratic
  • Key symptoms
    • High fever
    • Severe muscle stiffness (rigidity)
    • Confusion
    • Autonomic instability
  • NMS and SS do have similarities (hyperthermia, AMS, rigidity) but…
  • Not hard to differentiate NMS from Serotonin Syndrome
    • SS has marked hyperreflexia, clonus and myoclonus, NMS does not
    • SS (when severe) has opsoclonus, random saccades of the eyes, NMS does not
    • SS caused by an SSRI not antipsychotic
    • SS much more common, NMS is rare
  • NMS vs Catatonia
    • Very difficult to distinguish
    • Initially just hold antipsychotics
  • Treatment
    • Intubate when rigidity is affecting ventilation
    • Dantrolene consider when CK rapidly rising
    • Benzos are just as good
    • Bromocriptine rarely used
  • Post Recovery
    • Can restart an antipsychotic 2 weeks after recovery, rare for NMS to return.